.html,body,.parent{height:100%;overflow:hidden;}
.top{position:absolute;top:0;left:0;right:0;height:77px;}
.top_nav{position:absolute;top:40px;left:220px;right:0;height:39px;}
.left{position:absolute;left:0;top:77px;bottom:0px;width:220px;}
.right{position:absolute;left:220px;right:0;top:77px;bottom:0px;}
.main_content{position:absolute;left:0;right:0;top:0;bottom:0px;background: #fff;}
.footer{position:absolute;left:0;right:0;bottom:0px;height:30px;}
.bottom{position:absolute;left:0;right:0;bottom:0;height:0px;}
